In vitro and in vivo investigation of Persian manna plant silage as an alternative forage for fattening lambs

Abstract

The Persian manna plant (Alhagi maurorum, PMP) is a species with drought-resistant characteristics and distribution from Asia to America which is widely used in traditional medicine. As a result of recent droughts, many ranchers have become interested in using this plant for feeding their livestock. According to our knowledge, no scientific study has been done regarding the silage quality of PMP with natural-microbial additives. Rumen fluid may also be used as a low-cost and novel-natural microbial additive for improvement in silage quality. Therefore, we planned two in vitro and in vivo experiments to investigate PMP silage. In the first experiment, we ensiled PMP with molasses (M: molasses, 3%, 6%, and 9% of DM) plus rumen fluid (RF: rumen fluid, 3%, 6%, and 9% of DM) for 60 days with the aim of investigation of nutritional characteristics and its silage potential by in vitro methods. In the second experiment, we investigated the nutritional value of the selected superior silage from the in vitro section for animal experiments. The growth performance, nutrient digestibility, and ruminal fermentation parameters of forty male lambs were evaluated for substitution of 25%, 50%, 75%, and 100% forage with M6 +RF6 silage in a completely randomized design. Some mineral-chemical composition and digestive-fermentative parameters changed with ensiling PMP. The lowest NDF and ADF were observed in M6 +RF6 (P < 0.0001). Higher lactic acid production, total volatile fatty acids, aerobic stability, acid-base buffering capacity, metabolizable energy, Flieg point, and lower butyric acid, ammonia nitrogen, and pH were observed in M6 +RF6 compared to the control. Among the treatments, the highest dry matter intake, average daily gain, final weight, nutrient digestibility, and total volatile fatty acids were observed in lambs fed on the control diet. In total, PMP can be ensiled with molasses and rumen fluid well. As a result of the in vitro tests, a better nutritional value was relatively observed in M6 +RF6. The in vivo test also showed that M6 +RF6 can be substituted up to about 26% of the dietary DM without adverse effects on growth performance, nutrient digestibility, and ruminal fermentation parameters.